Officials in Lafourche and Terrebonne parishes are looking into residents' reports of earth tremors in the area this week.

So far, they have no answers.

A Lockport resident described feeling a sudden vibration that hit his house at 2 p.m. Wednesday.

Chris Boudreaux, Lafourche's director of Emergency Operations, said efforts to find a possible source - such as sonic booms from airplanes or vibrations from oilfield activity - have turned up nothing. Boudreaux said the U.S. Geological Survey reported no seismic activity, although it has few monitors in the area.

Paul Caruso, a geophysicist with the Geological Survey's National Earthquake Center, told The Courier that there are not many seismic monitors in south Louisiana because there is rarely any such activity in the area.